Display exhibits and booths used at tradeshows and exhibitions are preferably easily transportable, are preferably quickly and easily erected and collapsed, and are preferably light weight for ease of portability and to reduce shipping costs. Additionally, the area available to each exhibitor at tradeshows and exhibitions is limited. Accordingly, exhibitors desire to maximize the limited space available to them.
A common feature used by exhibitors is a backwall, which may be a simple hanging curtain, or a series adjacent retractable banners such as disclosed in U.S. Pat. No. 7,337,567 issued to Skyline Displays, Inc., or self supporting frames or structures with fabric or rigid panels. The backwall serves two primary purposes. First, it provides a large prominent surface on which company logos, promotional materials and images of the company's products, services or other eye-catching images may be displayed to attract visitors to the exhibitor's display area. Second the backwall serves to conceal extra promotional materials, supplies, packaging, containers and other items that the exhibitor does not want visitors to be able to view or access.
The space available behind the backwall is generally very limited because tradeshow rules often require display backwalls to be no more than three feet from the facility's walls or other structures, so that one exhibitor's backwall does not block the display of neighboring exhibitors. In any event, exhibitor's typically want to have the backwall as far back as possible to provide adequate space in front of the backwall for tables, chairs and other furnishings on which to display promotional materials and to provide adequate free space to allow exhibitor representatives and visitors to easily move around to view the promotional items and to mingle and discuss business.
Many exhibitors desire to project images on the backwall of their display area, such as their company logo, or other eye-catching images to promote their products or services and to attract visitors to the display area. Until the relatively recent development and availability of short-throw, wide angle projectors, most exhibitors that wanted to project an image on a backwall of their booth or display, they had to use a conventional front projection system which required the projector to be placed toward the front of the display area or booth in order to produce a large image on the backwall. However, when placing the projector at the front of the display area, shadows would be produced blocking the projected image anytime someone walked between the projector and the backwall.
With the relatively recent development and commercial availability of short-throw, wide angle projectors, exhibitors are now able to place the short-throw projector within a few feet of the backwall while still producing a large image on the backwall, thus significantly reducing the chance that the projected image will be blocked by shadows from people walking between the projector and backwall. However, with such systems, the short-throw projector still takes up valuable space within the display area that could be used for other purpose.
Furthermore, although rear projection screens are known and although rear projection screens would overcome the foregoing disadvantages of a conventional front projection system as well as a short-throw front projection system, the use of rear projection systems at tradeshows or exhibitions has been uncommon and heretofore unpractical, at least for most exhibitors, due to the cost and difficulty of setup of rear projection systems to produce a distortion free image. It should be appreciated that in order to produce an image on a rear projection screen that is not distorted, the screen must be planar and must be uniformly stretched without any distortions. The need for planarity and lack of distortion is due to the unique optically transmissive and light diffusive characteristics of rear projection screens which permit the image to be viewed through the screen, as opposed to being reflected as with a front projection screens.
Accordingly, there is a need for a relatively inexpensive projection backwall for use at tradeshows, exhibitions, and the like, which is collapsible and relatively light weight for ease of portability and which is quickly and easily erectable and collapsible, and, when erected, results in a substantially planar and distortion free surface that is able to display substantially distortion free projected images.